This invention relates in general to electrical circuit interrupters and in particular to a high speed contact driver for use in current limiting circuit interruption devices.
In the past, typical alternating current circuit breakers required the creation of a large mechanical gap between two electrical conductors, and could only interrupt an alternating current at a zero-crossing. More recently developed current limiting circuit interrupters, for example of the type shown in U.S. Pat. No. 4,375,021 to Pardini et al. (assigned to the assignee of the present invention and incorporated herein by reference), provide the capability of substantially immediately interrupting alternating currents of high magnitude without waiting for a current zero-crossing. These current limiting interrupters are typically complex in construction, and thus somewhat expensive to fabricate.
The above referenced application Ser. No. 684,307 (hereinafter referred to as "Howell") discloses a high speed contact driver for use in current limiting circuit interrupters. The contact driver of Howell, described in detail below, uses a pulse of current applied to a pair of closely spaced electrical conductors to cause these conductors to electromagnetically repulse one another and lift a bridging contact away from a pair of stationary contacts.
While Howell provides fast and reliable separation of electrical contacts, the nature of current limiting interrupters is such that faster, more reliable interruption is always better. Thus, any improvement over Howell which provides for faster, more reliable circuit interruption provides a substantial benefit to the art.